05000387/LER-2015-006, Regarding Loss of Safety Function Due to Inoperability of Both Trains of the Standby Gas Treatment System and a Loss of Safety Function of the Control Room Emergency Outside Air Supply System Due to Air Flow

Regarding Loss of Safety Function Due to Inoperability of Both Trains of the Standby Gas Treatment System and a Loss of Safety Function of the Control Room Emergency Outside Air Supply System Due to Air Flow

ML15334A115
Person / Time
Site:	Susquehanna
Issue date:	11/25/2015
From:	Franke J Susquehanna, Talen Energy
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
PLA-7417 LER 15-006-00
Download: ML15334A115 (5)

LER-2015-006, Regarding Loss of Safety Function Due to Inoperability of Both Trains of the Standby Gas Treatment System and a Loss of Safety Function of the Control Room Emergency Outside Air Supply System Due to Air Flow

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(v), Loss of Safety Function
3872015006R00 - NRC Website

text

NOV 2 5 2015 Jon A. Franke Site Vice President U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Susquehanna Nuclear, LLC 769 Salem Boulevard Berwick, PA 18603 Tel. 570.542.2904 Fax 570.542.1504 jon.franke@talenenergey.com SUSQUEHANNA STEAM ELECTRIC STATION LICENSEE EVENT REPORT 50-387/2015-006-00 UNIT 1 LICENSE NO. NPF-14 PLA-7417 TALEN~

ENERGY 10 CFR 50.73 Docket No. 50-387 Attached is Licensee Event Report (LER) 50-387/2015-006-00. On September 29, 2015, the Susquehanna Steam Electric Station (SSES) experienced a loss of the 'A' and 'B' trains of the Standby Gas Treatment System (SGTS) during the performance of two cross-divisional surveillance tests. In accordance with 10 CFR 50.72(b)(3)(v)(c), at 1456 hours0.0169 days <br />0.404 hours <br />0.00241 weeks <br />5.54008e-4 months <br /> on September 29,2015, an 8-hour Event Notification (#51432) was made to the NRC for any event or condition that could have prevented the fulfillment of the safety function of stmctures or systems that are needed to control the release of radioactive material. In addition, this LER is being submitted for a loss of safety function of the Control Room Emergency Outside Air Supply System which was identifed on September 30, 2015 at 0300 hours0.00347 days <br />0.0833 hours <br />4.960317e-4 weeks <br />1.1415e-4 months <br />.

There were no actual consequences to the health and safety of the public as a result of this event.

~his le~eetory comnllUnents.

. A. Franke Attachment: LER 50-387/2015-006-00 Copy:

NRC Region I Mr. J. E. Greives, NRC Sr. Resident Inspector Ms. T. E. Hood, Whited, NRC Project Manager Mr. M. Shields, PA DEP/BRP

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 0113112017 (02-2014)

, the NRC may not conduct or sQonsor and a person is not required to respond to the information collection.

6. LERNUMBER

3. PAGE YEAR I

SEQUENTIAL I REVISION NUMBER NUMBER 2 of 4 2015

• 006

• 00 There were no systems, structures, or components that were inoperable at the start of the event and contributed to the event.

EVENT DESCRIPTION

On September 29, 2015, at 0900 hours0.0104 days <br />0.25 hours <br />0.00149 weeks <br />3.4245e-4 months <br />, operations commenced surveillance test SE-030-0028 (24 Month Control Structure Ventilation System Operability Test Div II '8' SGTS). Performance of this test placed the Division II of the Control Structure ventilation system equipment in various alignments for data collection.

During the performance of SE-030-0028, at 0943 hours0.0109 days <br />0.262 hours <br />0.00156 weeks <br />3.588115e-4 months <br />, Instrumentation &Controls (I&C) personnel commenced testing per Sl-180-306 (24-Month Calibration of RWCU PCIS Secondary Containment Isolation and CREOASS Initiation on Reactor Vessel Water Level 2 and MSIV Isolation on Reactor Vessel Water Level1 for channels LITS-821-1 N026A and 821-1 N026C). This Sl tests the function of the reactor pressure vessel switches associated with primary containment isolation system actuations and secondary containment isolation actuations, which initiates the logic to start the Standby Gas Treatment System (SGTS).

At 1020 hours0.0118 days <br />0.283 hours <br />0.00169 weeks <br />3.8811e-4 months <br />, entered the Action Statement forTS 3.6.4.3 for the '8' train of the Standby Gas Treatment (SGTS) system to manual to adjust flow in accordance with test procedure SE-030-0028.

At 1030 hours0.0119 days <br />0.286 hours <br />0.0017 weeks <br />3.91915e-4 months <br />, control room personnel were notified that level instrument LITS-821-1 N026A failed its Sl-180-306 test acceptance criteria. This failed instrument channel is part of the initiation logic for the 'A' train of SGTS. Control room personnel then directed restoration from SE-030-0028 to return the '8' train of SGTS to operable status. However, there was no direction in the controlling surveillance procedure to return the '8' CREOASS controller to automatic, and therefore it remained in manual.

In accordance with TS 3.0.6, since SGTS is a supported function of the affected instrument, a loss of safety function determination was performed, and the 'A' train of SGTS was declared inoperable. As a result, both the 'A' and '8' trains of SGTS were inoperable and the Action Statement forTS 3.6.4.3, Condition D, was entered at 1050 hours0.0122 days <br />0.292 hours <br />0.00174 weeks <br />3.99525e-4 months <br />.

In accordance with 10 CFR 50.72(b)(3)(v)(c), at 1456 hours0.0169 days <br />0.404 hours <br />0.00241 weeks <br />5.54008e-4 months <br /> on September 29, 2015, Susquehanna Nuclear, LLC made an 8-hour Event Notification (EN#51432) to the NRC for any event or condition that could have prevented the fulfillment of the safety function of the Standby Gas Treatment System.

On September 30, 2015, during panel walkdowns, it was identified that the '8' CREOASS flow controller was still in manual and had not been restored to auto after completion of SE-030-0028 on September 29, 2015.

As a result, the Action Statement forTS 3.7.3 was entered for the '8' train being inoperable.

EVENT DESCRIPTION (cont.)

I REVISION NUMBER

- 00

3. PAGE 30F 4 In accordance with 10 CFR 50.73(a)(2)(v)(C), this LER is being submitted for an event or condition that at the time of discovery, could have prevented the fulfillment of the safety function of the Standby Gas Treatment System to control the release of radioactive material. This LER is also being submitted in accordance with 10 CFR 50. 73(a)(2)(v)(C), for a loss of safety function of the CREOAS system.

Sequence of Events 9/29/2015-0829 hours-Entered TS 3.3.2.2, Condition A for Sl-180-306.

0900 hour0.0104 days <br />0.25 hours <br />0.00149 weeks <br />3.4245e-4 months <br />s-Commenced surveillance SE-030-0028. Six hour Allowable Performance Times (APTs) were applicable forTS 3.3.6.1, 3.3.6.2, 3.3.7.1.

0943 hour0.0109 days <br />0.262 hours <br />0.00156 weeks <br />3.588115e-4 months <br />s-Commenced surveillance Sl-180-306.

1020 hour0.0118 days <br />0.283 hours <br />0.00169 weeks <br />3.8811e-4 months <br />s-Entered the Action Statement forTS 3.6.4.3 for the '8' train of the Standby Gas Treatment (SGTS) system to manual to adjust flow in accordance with test procedure SE-030-0028.

1030 hour0.0119 days <br />0.286 hours <br />0.0017 weeks <br />3.91915e-4 months <br />s-Instrument LITS-821-1 N026A was outside the acceptance criteria of Sl-180-306. I&C Supervisor discussed impact with control room personnel.

1050 hours0.0122 days <br />0.292 hours <br />0.00174 weeks <br />3.99525e-4 months <br /> - Discussed APT impacts and determine they were no longer applicable and the following TS action statements were entered forTS 3.3.6.1, 3.3.6.2 and 3.3.7.1, effective at 1030 hours0.0119 days <br />0.286 hours <br />0.0017 weeks <br />3.91915e-4 months <br />.

Directed the restoration of the '8' SGTS to normal standby lineup and the performance of SE-030-0028 was halted. TS 3.3.6.2, Condition A was entered effective 1030 hours0.0119 days <br />0.286 hours <br />0.0017 weeks <br />3.91915e-4 months <br />. This is a support system for SGTS. Since SGTS is a supported function of the affected instrument (LITS-821-1 N026A), the 'A' train of SGTS was declared inoperable. With both the 'A' and '8' trains of SGTS inoperable, TS 3.6.4.3, Condition D was entered since both the 'A' and '8' trains were inoperable.

1145 hour0.0133 days <br />0.318 hours <br />0.00189 weeks <br />4.356725e-4 months <br />s-The '8' train of SGTS was restored and declared operable and TS 3.6.4.3, Condition D was exited.

1228 hour0.0142 days <br />0.341 hours <br />0.00203 weeks <br />4.67254e-4 months <br />s-LITS-821 -1 N026A instrument was calibrated to within final tolerance, and the acceptance criteria were met.

1236 hour0.0143 days <br />0.343 hours <br />0.00204 weeks <br />4.70298e-4 months <br />s-Restored the 1 C004 Reactor Pressure Vessel Instrument Rack to service and was declared operable.

1237 hour0.0143 days <br />0.344 hours <br />0.00205 weeks <br />4.706785e-4 months <br />s-Exited TS 3.3.2.2, Condition A action statement.

Sequence of Events (cont.)

9/30/2015-I REVISION NUMBER

- 00

3. PAGE 40F 4 0300 hours0.00347 days <br />0.0833 hours <br />4.960317e-4 weeks <br />1.1415e-4 months <br /> - During panel walkdowns, it was identified that the 'B' CREOASS flow controller was still in manual and had not been restored to auto after completion of SE-030-0028 on September 29, 2015. As a result, the action statement forTS 3.7.3 was entered for the 'B' train being declared inoperable.

CAUSE OF THE EVENT

An apparent cause evaluation for this event is in progress. The results of the evaluation, including cause, corrective actions, and potential consequences will be provided in a supplement to this LER.

ANALYSIS/SAFETY SIGNIFICANCE

There were no actual consequences to the health and safety of the public as a result of this event An apparent cause evaluation for this event is in progress. The results of the evaluation, including cause, corrective actions, and potential consequences will be provided in a supplement to this LER.

CORRECTIVE ACTIONS

An apparent cause evaluation for this event is in progress. The results of the evaluation, including cause, corrective actions, and potential consequences will be provided in a supplement to this LER.

PREVIOUS SIMILAR EVENTS

None.